Combustion burner



July 9, 1963 w. D. KERVIN COMBUSTION BURNER 2 Sheets-Sheet 1 Filed Sept. 21, 1961 INVENTOR flfi. I n/kw July 9, 1963 w. D KERVIN COMBUSTION BURNER Filed Sept. 21. 1961 2 Sheets-Sheet 2 14 54 JMUM- m ATTORNEYS United States Patent 3,096,812 COMBUSTION BURNER Willis D. Kervin, Johnson City, Tenn., assignor to Carbonic Development Corporation, Johnson City, Tenn., a corporation of Delaware Filed Sept. 21, 1961, Ser. No. 139,629 2 Claims. (Cl. 158-108) This invention relates to combustion burners and more particularly to burners which direct a flame outwardly for flame treatment of an article.

Combustion burners have long been employed to apply a flame of high heat intensity to a specific work area. In such operation it is desirable to make optimum use of the reactant iuel mixture. Conventional burners in which flame travels straight from the point of ignition Within the burner to the burner month, are in many respects inefficient. For example, they fail to preheat the fuel reactants, flail to promote molecular chain reaction of the fuel, and provide little opportunity for turbulent mixing of the fuel reactants so as to insure complete burning. Thus the flame produced by such equipment is slow in reaching thermodynamic equilibrium, and a relatively long flame external of the burner is required. Due to the extended flame length, the area or region over which heat is released to the work is likewise extended which is an acute disadvantage for work in which concentration of intense heat over a restricted area of the work is desired.

It is a primary object of this invention to provide an improved combustion burner of greatly enhanced efliciency.

Another object of this invention is to provide an improved eombustion burner capable of producing a short flame providing intense heat.

Still another object of this invention is to provide an improved burner device which preheats and promotes molecular chain reaction of the fuel reactants, while insuring their thorough mixing.

A further object of this invention is to provide an improved combustion burner capable of attaining thermodynamic equilibrium in the combustion process with a relatively short external flame.

A still further object of this invention is to provide an improved combustion burner characterized by a flame of short length and high heat intensity, but which is relatively simple and inexpensive to manufacture.

Generally the combustion burner of this invention comprises a burner block defining a combustion chamber having a curved dome and a burner mouth opposite the dome and means for delivering ignited fuel along opposing walls of the combustion chamber toward the curved dome so that the ignited fuel is deflected at the apex of the curved dome out of the burner mouth.

Further objects, features, and attending advantages of the invention will become apparent by reference to the following detailed description and accompanying drawings, in which: 7

FIGURE 1 is a sectional view in side elevation of one embodiment of the invention,

FIGURE 2 is a sectional view taken on line 2--2 of FIGURE 1,

FIGURE 3 is a sectional view in side elevation of a modified embodiment of the invention,

FIGURE 4 is a sectional view taken on line 4-4 of FIGURE 3,

FIGURE 5 is a sectional view taken on line 5--5 of FIGURE 3.

With reference to FIGURE 1, there is generally indicated at one embodiment of the burner device of this invention. Burner device 10 includes a burner block composed of refractory material. Any suitable refractory 7 material may be used for the block so long as it meets 3,096,812 Patented July 9, 1963 requirements of high resistance to flame erosion and resistance to temperature and mechanical shock. It has been found that a high purity aluminum oxide castable refractory is suitable for this purpose.

Burner block 20* defines a hollowed-out combustion chamber 21 having at one end a curved dome 22 and at the other end an opening 23. Burner block 20 is con tained within a burner body or housing which includes wall means 30. The configuration of wall means 30 will be determined by the configuration of burner block 20. Thus, as in the illustrated embodiment of a generally cylindrical burner block 20, wall means 30 will likewise be cylindrical in shape. Any suitable material resistant to heat and mechanical shock may be used for wall means 30. In the cylindrical embodiment illustrated, a length of steel pipe is used.

The burner body also includes a cap 40 forming one end wall and a retaining ring or annulus 50 forming the opposite end wall of the burner body. One end of the combustion burner 10 is closed by the cap 40 which is attached about the rim of wall means 30. The opposite end of burner device 10 is closed by the retaining ring 50, which is attached to wall means 30 at the rim opposite cap 40. Any suitable materials may be used for cap 40 and annulus 56. For example, cold rolled steel has been found adequate for cap 40, but for annulus '50, which is subject to the heat of the burner flame, a high temperature melting stainless steel, or similar heat resistant material, is more desirable.

Suitable pas-sages are provided to supply fuel from an external source of fuel supply to the internal combustion chamber 21. In accordance with the invention, such fuel supply means includes an opening 41 in cap 40 through which passes a fuel supply pipe 42. Wall means 30 is sufiiciently long to provide a space 31 separating cap 40 from the outer end face of burner block 20. The space -31 provides a manifold. As best seen in FIGURE 2, burner block '20 is formed with a plurality of recesses or channels 24 extending axially along its outer periphery. Channels 24, communicating with space 31 and closed on their exterior side by wall means 3!}, allow a fuel mixture introduced through pipe 42, to pass along the outside of burner block 20 and in contact therewith. While the channels illustrated are tour in number, more or fewer may be provided as long as an adequate distribution and supply of fuel to the combustion chamber is insured.

As best seen in FIGURE -1, retaining ring or annulus 59 has a central hole or bore 51 which forms a mouth in registry with opening 23 of chamber 21, and is concentric with chamber 21 on an axis drawn through the apex of curved dome 22. Opening 51 of annulus 50 has a smaller diameter than opening 23 of chamber 21, so that a shoulder portion 54 of annulus 50 extends about the periphery defining the opening 23.

The outer diameter of annulus 50 near its upper portion 53 is equal to the distance between the inner walls of opposite passages 24 of burner block 28. An annular groove 52 extends radially inwardly from the outside diameter of annulus 50. Wall means 30 extends beyond the open end face of burner block 20 and attaches to annulus 50 at a flange portion 56. Thus, cylindrical wall means 30, together with the reduced diameter of annulus '59 at its upper portion '53 adjacent the burner block defines a space which communicates with the axial passages 24 and the annular groove 52.

About the periphery of shoulder portion 54 of annulus 50 there are provided a plurality of nozzles or ports 55, joining the space defined by groove 52 with the interior of chamber 21. Ports 55 are drilled at an angle such that gases entering chamber 21 from groove 52 are directed so as to impinge at an angle against the side walls of chamber 21. An angle of about with such side walls has been found to produce excellent results.

The arrangement of the retaining ring 50 and the ports 55 greatly enhances the flame retention capability of the burner. As the input pressure increases the back pressure against the ports correspondingly increases, which back pressure prevents or minimizes blowing off of the flame.

With reference now to FIGURES 3 through 5, there is illustrated an alternative embodiment of the invention. With reference to FIGURE 3 there is generally indicated at 100 a burner device which is elongated on one horizontal axis, rather than substantially cylindrical, as illustrated in the embodiments of FIGURES l and 2.

A burner block 120 is provided with a hollowed-out combustion chamber 121 having a curved dome 122 at one end, and at the opposite end an opening 123. The burner block 120 is surrounded by a burner body or housing comprising a wall means 130, a cap 140 fortning one end wall of the burner body and a retaining ring or annulus 150 which forms the opposite end wall of the burner body.

The fuel supply system is identical to that described with reference to FIGURES 1 and 2. Passage means for supplying a fuel mixture to the combustion chamber 121 is provided by a pipe 142 passing through a hole 141 in cap 140. Fuel supplied through pipe 142 enters a space or manifold 131. between cap 146 and burner block 12%. From such space the fuel enters axial passages defined by wall means 130 and channels 124 provided along the outer periphery of burner block 120. From channels 124 the fuel enters a chamber in annulus 150. Such chamber is formed by the reduced diameter of the annulus at 153, and the groove 152 extending radially inwardly from the outer periphery of the annulus 150. The groove 152 communicates with combustion chamber 121 by means of a plurality of nozzles or ports 155 extending through shoulder portion 154 of annulus 150. The ports 155 are oriented to direct fuel against opposing walls of the combustion chamber toward the dome 122 in the same manner as the ports 55 previously described. Wall means :130' is attached to annulus 150 at a flange portion 156.

The elongated configuration of openings 123 of the combustion chamber 121 and opening or month 151 of annulus 150 gives the burner mouth of this embodiment a much longer and relatively narrow shape as compared to the circular shape of the burner mouth of the embodiment illustrated in FIGURE 2. It will be apparent that the various embodiments will have application in different situations. Thus, for example, the circular burner mouth could be used with an indexing conveyor, directing its concentrated flame onto each passing work unit at a time, whereas the elongated burner mouth could be used with a constant-moving conveyor, directing its flame against work units traveling the horizontal length of the elongated burner mouth.

It will be apparent that many other sizes and configurations of the burner opening are possible without departing from the concept set forth.

The operation of the burner device of this invention will now be described in detail with reference to the embodiment illustrated in FIGURES 1 and 2.

Burner fuel admitted through pipe 42 enters chamber 31, and thence passes along channels 24. It will be apparent that the heat of combustion within chamber 21 will pass by conduction through burner block 20 so that a portion will be given up to the fuel passing through chamber 31 and channels 24. In this manner the fuel reactants are preheated, which facilitates the complete combustion process after the reactants enter the burned chamber.

From channels 24, fuel enters grooves 52 and is directed by the inclined ports 55 against opposed walls of combustion chamber 21. Fuel exiting from the ports 55 is ignited by any suitable means, as by a pilot device. It will be apparent that ignition need be provided only initially, since, once combustion has begun, the flame within chamber 21 together with the high temperature of the chamber walls with which the fuel comes in contact causes ignition without the aid of a pilot or other supplemental ignition means.

As best seen in FIGURE 1, the angle at which vents 55 are drilled causes fuel supply to the chamber 21 t0 impinge at an angle against the side walls of chamber 21. The fiame of the ignited fuel then sweeps the chamber wall, converging at the axis dome 22. Since the ports are disposed all about the rim or shoulder 54, the flame converges at the dome and is deflected downwardly in a single concentrated stream through the opening 23 and out of the burner mouth 51.

The rapid change of direction which the fuel undergoes from the time it enters the burner device until it is ignited results in a high degree of turbulent mixing. Moreover, the change of direction which the ignited fuel makes within the chamber further promotes turbulent mixing of the incoming unreacted and partly reacted fuel.

Since the flame must effectively travel twice the length of the chamber, there is afforded within the chamber an unusually long time within which completion of the combustion reaction may take place, thus further insuring complete burning. It will be apparent that the flame sweeping the chamber wall brings it to an intense degree of heat. The extensive surface of this heat chamber wall against which the reactants impinge promotes molecular chain reaction, further insuring complete burning. Furthermore, radiant heat within the chamber acting upon the flame insures an exceptionally high degree of heat intensity of the flame issuing from the burner mouth.

Thus, complete and eflicient burning, obtainable in conventional burner apparatus only by permitting an undesirably long length of flame travel, is in this invention obtained by a device which insures complete burning of fuel reactants and intense flame heat in a confined and effectively short length of external flame travel. The intense short flame emanating from the burner may be directed on a small portion only of an article to be treated. For example, the flame can be impinged directly on the lip of a bottle to melt mold imperfections without unduly heating the neck or shoulder of the bottle.

The apparatus of the invention has many uses including without limitation fire polishing glass articles such as bottles, gear hardening, spot heat treating, strip annealing and brazing of metals, and sealing evacuated glass chambers.

While I have illustrated the invention in two specific embodiments, it will be apparent to those skilled in the art that various modifications may be made without departing from the scope of the invention which is defined solely by the appended claims.

I claim:

1. A combustion burner having a longitudinal axis and comprising a burner block of refractory material defining a combustion chamber having side walls generally parallel to said axis, a curved dome at one end of said chamber and an opening at the opposite end of said chamber, a burner body including side walls means surrounding said burner block, a first wall at one end of said body defining a mouth in registry with said opening and a second wall at the other end of said body having an inlet to admit tburner fuel, passage means communicating with said inlet and extending in said burner block longitudinally of said axis along and outside of said chamber to provide direct heat exchange between the refractory material of said burner block and the fuel in said passage means, said first wall providing a plurality of ports communicating with said passage means and spaced around the periphery of said opening, said ports being oriented to direct fuel against opposing walls of said chamber and toward said References Cited in the file of this patent UNITED STATES PATENTS 2,210,301 Newby Aug. 6, 1940 6 Hess Sept. 17, 1940 Bowman Apr. 2, 1946 Grantham June 17, 1947 Clarkson Apr. 17, 1951 Knight Mar. 10, 1959 K-leist Feb. 6, 1962 FOREIGN PATENTS Great Britain Feb. 3, 1927 

1. A COMBUSTION BURNER HAVING A LONGITUDINAL AXIS AND COMPRISING A BURNER BLOCK OF REFRACTORY MATERIAL DEFINING A COMBUSTION CHAMBER HAVING SIDE WALLS GENERALLY PARALLEL TO SAID AXIS, A CURVED DOME AT ONE END OF SAID CHAMBER AND AN OPENING AT THE OPPOSITE END OF SAID CHAMBER, A BURNER BODY INCLUDING SIDE WALLS MEANS SURROUNDING SAID BURNER BLOCK, A FIRST WALL AT ONE END OF SAID BODY DEFINING A MOUTH IN REGISTRY WITH SAID OPENING AND A SECOND WALL AT THE OTHER END OF SAID BODY HAVING AN INLET TO ADMIT BURNER FUEL, PASSAGE MEANS COMMUNICATING WITH SAID INLET AND EXTENDING IN SAID BURNER BLOCK LONGITUDINALLY OF SAID AXIS ALONG AND OUTSIDE OF SAID CHAMBER TO PROVIDE DIRECT HEAT EXCHANGE BETWEEN THE REFRACTORY MATERIAL OF SAID BURNER BLOCK AND THE FUEL IN SAID PASSAGE MEANS, SAID FIRST WALL PROVIDING A PLURALITY OF PORTS COMMUNICATING WITH SAID PASSAGE MEANS AND SPACED AROUND THE PERIPHERY OF SAID OPENING, SAID PORTS BEING ORIENTED TO DIRECT FUEL AGAINST OPPOSING WALLS OF SAID CHAMBER AND TOWARD SAID DOME SO THAT WHEN SAID BURNER IS OPERATING THE FUEL IS IGNITED AS IT ENTERS SAID CHAMBER AND THE RESULTING FLAME SWEEPS SAID OPPOSING WALLS AND IS DEFLECTED AT THE APEX OF SAID DOME THROUGH SAID MOUTH. 